Determination of the cardioactive prototype LASSBio-294 and its metabolites in dog plasma by LC-MS/MS: application...

In this work we describe the evaluation of the pharmacokinetics of a novel cardioactive compound of the N-acylhydrazone class, LASSBio-294, using high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) in dog plasma for the first time. Separation was achieved on a ZORBAX Rapid Resolution High Definition (RRHD) SB-C18 (50mm×2.1mm, 1.8μm) reversed-phase column at 20°C with methanol-10mM ammonium acetate solution (65:35, v/v) at a flow rate of 1.0mL/min. Detection was performed using an electrospray ionization (ESI) operating in positive ion multiple reaction monitoring (MRM) mode by monitoring the ion transitions from m/z 275.2→149.1 (LASSBio-294) and m/z 152.0→110.0 (acetaminophen, internal standard). The calibration curve of LASSBio-294 in plasma showed good linearity over the concentration range of 1.25-800ng/mL. The validated method was successfully applied to a pre-clinical pharmacokinetic study of the cardioactive prototype LASSBio-294 in beagles after oral administration. The main pharmacokinetic parameters t(1/2), C(max) and AUC(0-24) were (5.74±0.55)h, (547.66±35.12)ng/mL and (1621.77±41.66)ngh/mL, respectively.